Research Interests

Publication list

CV

 
Imaging with coherent X-rays

X-rays have been used for imaging ever since they were discovered, more than a century ago. With their relatively weak interaction with matter and their short wavelength, X-rays are perfectly fit for high-resolution imaging in 2D, and especially 3D (tomography), of thick objects.

Modern synchrotron sources are able to produce X-rays that have good transverse and longitudinal coherence properties. The ability of confining the photons to the smallest possible phase space volume opens the possibility of modelizing accurately and unabiguously the interaction of the incoming wave with a sample. This opportunity has been seized in the last few years to create a different, lensless, mode of imaging. Such techniques, now most commonly described as "Coherent Diffractive Imaging" use "software lenses" to eliminate sources of image deteriorations brought about by X-ray lenses.

My research focuses on the application of some of these lensless techniques and on the data analysis techniques needed for image reconstruction. Currently of particular interest to me is the application of ptychography for high-resolution, and high-contrast 3D imaging.

 
Ptychography
A ptychography reconstruction This is the phase part of a complex-valued reconstruction of a gold Fresnel zone plate. The data was measured at the cSAXS beamline at PSI.
image

Introduced in electron microscopy by Hegerl and Hoppe in the early 1970s, "ptychography" (pronounced "tychography") is an imaging method that combines diffraction data from multiple datasets obtained by scanning a finite illumination on an extended specimen. It was recognized early on that this approach provides sufficient overdetermination to solve the phase problem. Yet efficient algorithms to do so appeared only a few years ago. In the last few years, my colleagues and I have developed the method further, and devised an improved reconstruction method that extracts from the data both the image of the specimen and the illumination function.

The main hurdles for application of ptychography have now been cleared, and it is routinely applied at the cSAXS beamline at the Swiss Light Source, where I did my first post-doc. Ptychography setups are now planned or under construction in most major synchrotron facilities, often in combination with other scanning methods, such as fluorescence mapping or scanning transmission X-ray microscopy (STXM).

 
 
  • P. Thibault, M. Guizar-Sicairos. Maximum-likelihood refinement for coherent diffractive imaging. New J. Phys. 14 , 063004, 2012. [ download ]
  • A. Diaz, P. Trtik, M. Guizar-Sicairos, A. Menzel, P. Thibault, O. Bunk. Quantitative x-ray phase tomography. Phys. Rev. B 85, 020104, 2012.
  • B. Kaulich, P. Thibault, A. Gianoncelli, M. Kiskinova. Transmission and emission X-ray microscopy: imaging modes and contrast mechanisms in real space and diffraction. J. Phys. D 23, 083002, 2011.
  • M. Dierolf, A. Menzel, P. Thibault, P. Schneider, C. M. Kewish, R. Wepf, O. Bunk, F. Pfeiffer. Ptychographic X-Ray Computed Tomography at the Nano-Scale, Nature 467, 436–440, 2010.
  • P. Thibault, V. Elser, X-ray diffraction microscopy. Annual Review of Condensed Matter Physics 1, 237–255, 2010.
  • A. Menzel, C.M. Kewish, M. Dierolf, P. Thibault, O. Bunk, P. Kraft, B. Henrich, E.F. Eikenberry, C.Brönnimann, K. Jemovs, C. David, O. Marti and F. Pfeiffer, Scanning Transmission X-Ray Microscopy with a Fast Framing Pixel Detector. Ultramicroscopy 110, 1143–1147, 2010.
  • C. Kewish, P. Thibault, O. Bunk, F. Pfeiffer. Potential for two-dimensional crystallography of membrane proteins at future X-ray free electron laser sources. New J. Phys. 12, 035005, 2010.
  • M. Dierolf, P. Thibault, A. Menzel, C. M. Kewish, K. Jefimovs, I. Schlichting, O. Bunk, F. Pfeiffer. Ptychographic coherent diffractive imaging of weakly-scattering specimens. New J. Phys. 12, 035017, 2010.
  • C. Kewish, P. Thibault, M. Dierolf, O. Bunk, A. Menzel, J. Vila-Comamala, K. Jefimovs, F. Pfeiffer. Characterization of the complex wavefield in the focus of reflective hard X-ray optics. Ultramicroscopy 110, 325–329, 2010.
  • K. Giewekemeyer, P. Thibault, S. Kalbfleisch, A. Beerlink, C. M. Kewish, M. Dierolf, F. Pfeiffer, T. Salditt. Quantitative Biological Imaging by Ptychographic X-ray Diffraction Microscopy. Proc. Natl. Acad. Sci. USA. 107, 529–534, 2010.
  • P. Thibault, M. Dierolf, C. M. Kewish, A. Menzel, O. Bunk, F. Pfeiffer. Contrast mechanisms in scanning transmission X-ray microscopy. Phys. Rev. A 80, 043813, 2009. [ download ]
  • P. Thibault, M. Dierolf, O. Bunk, A. Menzel, F. Pfeiffer. Probe retrieval in ptychographic coherent diffractive imaging. Ultramicroscopy. 109, 338-343, 2009.
  • P. Thibault, M. Dierolf, A. Menzel, O. Bunk, C. David, F. Pfeiffer. High-resolution Scanning X-ray Diffraction Microscopy.Science 321, 379-382, 2008. [ download ]
  • P. Thibault, I. Rankenberg. Optical Diffraction Microscopy in a Teaching Lab. Am. J. Phys. 75, 827-832, 2007. [ download ]*
  • V. Elser, I. Rankenburg, P. Thibault. Searching with Iterated Maps. Proc. Natl. Acac. Sci. USA 104, 418-423, 2007. [ download ]
  • P. Thibault, V. Elser, C. Jacobsen, D. Sayre, D. Shapiro. Reconstruction of a yeast cell from x-ray diffraction data. Acta Cryst. A62, 248-261, 2006. [ download ]
  • D. Shapiro, P. Thibault, T. Beets, V. Elser, M. R. Howells, C. Jacobsen, J. Kirz, E. Lima, H. Miao, A. M. Nieman, D. Sayre. Biological imaging by soft x-ray diffraction microscopy. Proc. Natl. Acad. Sci. USA 102, 15343-15346, 2005. [ download ]
  • Q. Shen, I. Bazarov, P. Thibault. Diffractive imaging of nonperiodic materials with future coherent x-ray sources. J. Synchrotron Rad. 11, 432-438, 2004. [ download ]
  • P. Thibault, L. J. Lewis. Stability of strained heteroepitaxial systems in (1+1) dimensions. Phys Rev. B 70, 035415, 2004.
  • S. Gravel, P. Thibault. Integrability and linearizability of Lotka-Volterra system with a saddle point with rational hyperbolicity ratio. J. Differ. Equations 184, 20-47, 2002.
 
© Pierre Thibault 2011